I asked this question on the weaver space forum 3 days ago but nobody has replied, so I thought I would try here.
I’ve just created a test page to see how image compression affects visual quality when saved at retina resolution but something really strange has occurred and I am not sure what is going on.
The page is at http://sunnymede.net/retina/ and if I visit the page using FireFox on a non-retina display the images are sharp but if I use Safari or Chrome they appear sharp for about a second before suddenly becoming softer.
If I click on the edge of the browser window in Safari or Chrome and drag it to make the window wider or narrower it instantly sharpens up until I release the window, at which point it becomes softer again.
This is done using the latest version of Foundation and I have never seen anything like this before in Rapidweaver. The original images are 1000 x 667 and they have all been set as 500 x 333 for browser viewing. They look totally OK when previewed inside RW or when viewed on a retina display.